1. Technical Field
The disclosure relates to a decorative resin molded article given an appearance with a concave and convex impression on the surface thereof, and to a method for producing the article.
2. Related Art
Heretofore, for imparting an appearance with a concave and convex impression to the surface of a synthetic resin molded article, there is known a method of previously forming concaves and convexes on the cavity surface of an injection mold and giving the concave and convex pattern to the surface of the injection molded article. In this method, the concave and convex pattern could be given to the planar section of the molded article, however, the concave and convex pattern is difficult to impart to the side section including curved surface shape parts thereof. This is because, when the molded article is drawn out from the mold and when the molded article has concaves and convexes on the side thereof, then the article is difficult to draw out from the mold, therefore bringing about a problem in operation.
On the other hand, as one method of decorating the surface of a synthetic resin molded article, there is known a method of arranging a previously-decorated resin sheet inside a mold followed by injecting a synthetic resin into the mold to thereby integrate the decorated resin sheet and the synthetic resin injection-molded body (sheet-insert molding method).
For example, JP-A 2003-145573 discloses an insert-molded article, for which a sheet decorated with a UV-curable color ink is used and set in a mold with the color ink layer thereof serving as a decorative layer kept facing inside and a resin injection-molded body is laminated and integrated on the decorative layer. JP-A 2008-272946 discloses a decorating method that includes providing a decorative layer on the back of a resin sheet through ink jet printing with a UV-curable ink, then providing a binder layer thereon, and laminating and integrating a resin injection-molded body on the side of the binder layer. In that manner, heretofore, in case where a decorated resin sheet is insert-molded, generally, the resin sheet is arranged in a mold with the decorative layer thereof kept facing the side of the resin to be injected therein, and in that condition, the resin is injection-molded so that the decorative layer is provided on the inner face of the resin sheet.
Accordingly, in the decorative resin molded article produced according to the above-mentioned sheet-insert molding method, the design with the decorative layer is expressed outside via the resin sheet, and is therefore influenced by the transmittance and the like of the resin sheet.
JP-A 07-032548 discloses a technique of laminating a UV-curable resin layer having a concave and convex pattern on one side of a transparent resin sheet followed by laminating and integrating the resulting laminate sheet with a resin injection-molded body. The laminate sheet has a sheet-like UV-curable resin layer having, on one side thereof, a concave, and convex pattern made with an engraved roll, in which, however, the color pattern and the concave and convex pattern are not synchronized. In addition, the concave and convex pattern face of the laminate sheet is made to face the side of the resin to be injected, and in that condition, the resin injection-molded body is laminated and integrated with the sheet.
JP-A 2008-105415 discloses a technique of preparing a decorative sheet by sequentially laminating a decorative layer of a print layer and an adhesive layer on an acrylic resin film, then providing a concave and convex pattern on the acrylic resin film by embossing on the surface opposite to the decorative layer thereof, and laminating and integrating a resin injection-molded body on the adhesive layer of the acrylic resin film. In this reference, the concave and convex pattern is formed on the surface side of the obtained, decorative resin molded article; however, the concave and convex pattern is formed by embossing and is not synchronized with a color pattern. And in addition, in this reference, the resin injection-molded body is laminated and integrated on the side of the print layer serving as a decorative layer. JP-A 2004-276416 also discloses a technique of forming a fine concave and convex layer on the surface of a decorative resin molded article; however, also in this reference, the pattern layer serving as a decorative layer is not synchronized with the concave and convex pattern on the surface of the article, and in addition, the resin injection-molded body is laminated and integrated with the decorative layer.
JP-A 2004-042409 discloses a technique of providing a surface protective layer formed of a UV-curable resin on one side of a resin sheet, forming a fine concave and convex pattern on the surface protective layer by pressurization under heat, then UV-curing the surface protective layer and providing a decorative layer having a pattern synchronizing with the concave and convex pattern on the other side of the resin sheet, and laminating and integrating a resin injection-molded body on the decorative layer. However, in this reference, the region having the fine concave and convex pattern and the decorative layer are synchronized so as not to overlap with each other between one side and the other side of the resin sheet. Accordingly, this differs from a technique, of providing colored convex projections on one side of a resin sheet to thereby provide, on that one side thereof, a design of a color pattern and a concave and convex pattern synchronizing with each other. In addition, in this reference, the resin injection-molded body is laminated and integrated on the decorative layer side, liken in the above-mentioned JP-A 2008-105415 and JP-A 2004-276416.